Dust control floor mats having a pile side and a rubber backing are generally used in access ways where people tend to brush or scrape their feet in order to prevent carrying moisture and/or dirt into other areas of the premises. Normally these mats are located in areas of high pedestrian traffic such as doorways.
The art includes a number of configurations and features for various floor mats. Some patents which are believed to be illustrative of known mats include U.S. Pat. Nos. 3,306,808 to Thompson, et al. issued Feb. 28, 1967; 4,741,065 to Parkins issued May 3, 1988; 4,886,692 to Kerr et al. issued Dec. 12, 1989; 5,227,214 to Kerr et al. issued Jul. 13, 1993; and 5,305,565 to Nagahama et al. issued Apr. 26, 1994; the teachings of all of which are incorporated herein by reference.
As will be appreciated, dust control mats by their nature must undergo frequent repeated washings and dryings so as to remove the dust deposited during use. These mats are generally rented from service entities which retrieve the soiled mats from the user and provide clean replacement mats on a frequent basis. The soiled mats are thereafter cleaned and dried in an industrial laundering process and then sent to another user in replacement of newly soiled mats.
Dust control mats have had two significant problems arising from frequent washings and harsh environments of use. First, the energy required to wash and dry a typical floor mat is significant due to the overall mass of the mats. This overall mass is made up of the mass of the mat pile, the mass of the carrier fabric into which the mat pile is tufted, and most significantly, the mass of the rubber backing sheet which is integrated to the carrier fabric under heat and pressure. As will be appreciated, a reduction in the overall mass of the floor mat will result in a reduced energy requirement in washing and drying the mat. Moreover, a relative reduction in the mass of the rubber backing sheet (i.e. the heaviest component) will provide the most substantial benefit. The floor mat of the present invention includes a rubber backing sheet which has a specific gravity which is approximately 25 percent less then the rubber sheets of typical prior floor mats. Accordingly, the overall energy requirements associated with the cleaning and handling of these mats is substantially reduced over that of prior mats.
The second problem which is encountered is the deterioration of the carbon--carbon double bonds in the matrix of the rubber backing sheet due to the exposure of the sheets to an oxidizing environment during use and cleaning. Specifically, the exposure of the mats to oxidizing agents during the washing and drying process tends to cleave the carbon--carbon double bonds of the rubber sheet thereby substantially embrittling the rubber which leads to cracking under the stress of use. In addition to the laundering process, the exposure of the mats to oxygen and ozone, either atmospheric or generated, during storage and use leads to cracking over time. The mat of the present invention incorporates a rubber backing sheet which provides enhanced protection against oxygen as measured by standard ozone resistance tests and is thereby believed to substantially prolong the useful life of the mat. Accordingly, the mat of the present invention represents a useful advancement over the prior art.